LDVV_Message |
Message from Dale Van Vleck
This was the message initially sent to those requesting the MTDFREML programs – some of this is now outdated, but it is included for historical reasons and for context.
This is a message I have sent to others who want to learn about MTDFREML.
You should receive 15 messages. These will include instructions; FORTRAN code; examples of data, answer and output files; and Word or Word Perfect versions of a detailed manual. The ninth message will describe how to download programs compiled using an 'include' file called 'param.dat'. My server detects and will not forward compiled programs in zipped files or with the extension of 'exe' changed. The 'param.dat' file sets maximums for number of traits, number of animals in the pedigree file, number of fixed and random factors, and number of levels for the factors. The parameters for the compiled programs are for a maximum of 2 traits and will handle most experimental data sets. For larger data sets, you will need to recompile the Fortran statements or find someone to do it for you.
For multiple trait analyses to estimate variance components and genetic parameters, we recommend doing 2-trait analyses of all pairs of traits because of time needed to obtain global convergence and because of possible singularity problems. Estimates from those analyses can be used to create genetic, etc., covariance matrices for multiple trait genetic evaluations. Predicted breeding values, etc., are obtained from solving the mixed model equations using created using (co)variance components you think are best. To do that you will need to recompile or have someone recompile for you.
Some students and visitors made a copy of my notes used in teaching workshops on MTDFREML. Their notes were better than mine so we have made a file of the notes which are easier to follow than the manual. You will also receive powerpoint presentations that provide an overview of the 'notes'.
The programs are relatively easy to use once the data file is set up correctly. The easiest way to learn is to have someone who has used the programs 'look over your shoulder'. Then 'trial and error' will make you an expert. At that point (or earlier if you have no one to help you), my recommendation is to read the notes to give you an idea of what the programs do. Then go through the PowerPoint slides. Follow that by going through the notes again but more thoroughly. To obtain more depth the chapter in the manual that goes through several examples would be useful. The chapter on the theory will give you a basis for understanding what is happening when you run the programs.
There may be other people in your country or area who use the program. If you have any trouble they may be closer than I am and might be willing to help. I have a record of many people who have the programs. Nevertheless, I will help in any way I can.
Good luck,
Dale
Dale Van Vleck
A-218 Animal Sciences
Lincoln, NE 68583-0908
phone: 402-472-6010
fax: 402-472-6362
e-mail: dvan-vleck1@unl.edu